NASA has discovered the first earth-size planets outside of our solar system. The discovery was made as part of NASA's Kepler mission and involves the discovery of two planets currently named after the project: Kepler-20e and Kepler-20f. If the Kepler name sounds familiar, that's because NASA also recently announced the discovery of Kepler-22b, the most Earth-like planet discovered to date. Kepler 22b is orbiting a star similar to our sun, and is capable of possessing liquid water, an essential feature for life to exist on a planet.